RESEAU FRANÇAIS DE
MECANOSYNTHESE
Lettre N°97
Avril 2003
189 Groupes de Recherche
(dont 115 à l'étranger / 34 Pays)
Bureau du RFM : E. Gaffet (Président)
G. Le Caër (Secr. Gén.), A.R. Yavari (Trés.)
International Editorial LRFM Committee
P. Balaz - Institute of Geotechnics - Slovak Academy of Sciece - Slovakia
G. Le Caër - GMCM UMR CNRS 6626 - Rennes - France
A. Calka - Dpt Materials Engineering - Univ. Wollongong - Australia
E. Gaffet (Coord.) - Nanomaterials Research Group - UMR 5060 CNRS / UTBM - France
S.H. Hong - Dpt Materials Science and Engineering - KAIST - Korea
E. Ivanov - Tosoh - USA
M. Senna - Faculty of Science and Technology - Japan
L. Takacs - Dpt Physics - Univ. Maryland – USA
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Bulletin d'adhésion 2003 / Subcription Print
(à retourner à l'adresse suivante - to be sent at the following address) :
Eric GAFFET
CNRS UMR5060 « Métallurgies et Cultures »
Nanomatérials Research Group
Site de Sévenans (UTBM) - F90010 - Belfort Cedex - France
Nom/Name : .........................................Prénom / First Name : ..................................
Adresse complète / Full Address :
....................................................................................
Téléphone/ Phone: ................................Télécopie (Fax) : .................................
e_Mel. / e-Mail : .......................................................................................
désire adhérer au Réseau Français de Mécanosynthèse / want to become a member of the French Mechanical Alloying Network
Chèque ci joint / Check enclosed in the amount of 20 Euros (20€)
The check has to be to the order to : Reseau Francais de Mecanosynthèse
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Le site web du RFM est :
http://www.bls.fr/amatech
Rubrique Pages Sciences et Techniques pour l'Ingénieur (Rubrique Sciences)
 vous y trouverez les anciennes lettres du RFM (accessible par Adobe Acrobat), les statuts du RFM ainsi que les annonces
concernant les JRFM'2001 et quelques éléments mis a jour régulièrement concernant les derniers résultats dans ce domaine.
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-2-
Vario-broyeur planétaire
Pulverisette 4

Un broyeur planétaire avec de nouvelles caractéristiques :
la possibilité de paramétrer les vitesses de rotation des bols de broyage et du plateau de façon
tout à fait individuelle

sollicitation de l’échantillon réglable au choix (friction et/ou choc)

finesses finales: < 1 µm (en fonction du matériels)

activation mécanique et mécanosynthèse

Interface RS232 pour une communication avec un PC afin de paramétrer et contrôler
la pulverisette 4“
Avec ce broyeur planétaire high-tech, vous atteindrez des résultats
uniques, impossible à obtenir avec tout autre broyeur planétaire.
QuickTime™ et un décompresseur
TIFF (LZW) sont requis pour visualiser
cette image.
Distributeur en France
Fisher Scientific LABOSI
12, avenue Gay Lussac
Zac clé de St Pierre
78996 Elancourt Cedex
Tel. 01 30 13 24 0
Fax.: 01 30 13 26 00
Emai: ventes@fr.fishersci.com
<www.fr.fishersci.com>
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-3Press Release
FRITSCH: Your specialist in the processing laboratory
FRITSCH is the world-wide leading manufacturer of
instruments for sample preparation and particle size analysis in
the laboratory. Since 80 years now, the company is
concentrating on the three product groups and identified with
the brand names of “pulverisette”, “analysette” and “laborette”
in research and industrial laboratories. The FRITSCH name is
synonymous with technical competence and economical
efficiency in all matters in the field of
 milling
 particle sizing
 dividing
Because FRITSCH operates throughout the world, they have
the unique advantage of vast experience in a wide variety of
scientific disciplines which enables them to offer constructive
solutions to ease problem solving. FRITSCH laboratory
instruments ensure proven reliability and innovative technology
in combination with simple operation.
Also this year FRITSCH are again from May 19th -24th, 2003 in Frankfurt on the ACHEMA in hall
6.1, booth no. J10-J12. They are going to disclose the secret of their numerous new developments. Don’t
miss this great event. New design and a number of innovative and practice oriented developments are
shown.
Here a small glance of our developments:
 Laser-Particle-Sizer “analysette 22” NanoTec
The world’s first laser measuring instrument for particle size distributions
and particle shape detection in a single process ! Completely new sensor
geometry and revolutionary software make this world premiere possible,
and we are presenting it for the first time at ACHEMA 2003.
 Laser-Particle-Sizer “analysette 22” COMPACT
Our standard model with the unbeatable price-to-performance
ratio enters the market with a complete overhaul and shows
what even a small budget can still do in particle measurement
technology.
 Clamping lid for “analysette 3” Vibratory Sieve Shaker
Our sieve shakers have become in the meantime to small
“high-tech”-instruments compared with earlier models or some
competing products. The most important technological gap
still present has now been closed with a new, high-quality
sieve tensioning mechanism.
 Mini Mill “pulverisette 23”
Earlier there was the legendary (East German) “Ardenne” mill,
and then there was nothing left on the entire world market.
We now present again a real minimum quantity mill that still
allows a suitable recovery even for forensic applications.

Vibrating Cup Mill “pulverisette 9”
Our new model is the world’s only vibration cup mill with
frequency converter control. This allows the vibration
frequency of the motor to be optimally adapted to the load
(grinding elements and grinding material) and the grinding is
performed in a minimum of time.

Cutting Mill “pulverisette 15”
Our decades of experience in the production of cutting mills
have been invested in our new model with significantly
improved grinding material feeding and grinding material
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-4-
recovery. The head of our laboratory is excited by this
instrument.

Cross Beater Mill “pulverisette 16”
This robust and easy-to-use mill is a true workhorse in any
processing laboratory for solids. It offers good results where
other mills have already failed, particularly with adhesive or
moist samples. We recommend a test grinding in our
applications laboratory.
Drop in – you will be surprised.
Please visit us at:
ACHEMA 2003 • 19. - 24.05.2003 • Frankfurt/Main • Exhibition Centre • hall 6.1, booth no.
J10-J12
JRFM 2003 • 03. - 04.06.2003
8èmes Journées du Réseau Français de Mécanosynthèse Amiens Pôle Scientifique
Faculté des Sciences, Amiens, France
Contact: FRITSCH GmbH
Manufacturers of Laboratory Instruments
Andrea Köhler
Industriestrasse 8  D-55743 Idar-Oberstein • Germany
Phone: ++49/67 84/70-146  Fax: ++49/67 84/70-11
E-Mail: info@fritsch.de  Internet: http://www.fritsch.de
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-5-
POST-DOC
PROGRAMME DE RECHERCHE
mailto:Luc.aymard@u-picardie.fr
Préparation par mécanosynthèse de nanoparticules à applications en stockage de l’énergie dans
les batteries Li-ions et les piles à combustible.
On observe ces dernières années un développement exponentiel des équipements électroniques
portables, un intérêt croissant pour le véhicule électrique, ou plus récemment pour des applications
embarquées ou terrestres des piles à combustibles. Les technologies Ni-MH et Li-ions couvrent
actuellement le marché de l’électronique portable sans avoir convaincu dans le domaine du transport.
Aussi, le récent essor du stockage de l’hydrogène dans les piles à combustibles ouvre aujourd’hui de
nouvelles perspectives et suscite un réel espoir pour ces applications en présentant comme principal
argument celui de respecter l’environnement
Le projet de recherche proposé consistera à mettre au point par mécanochimie et électrochimie de
nouveaux matériaux nanométriques à base de magnésium et/ou de lithium pouvant être utilisés comme
électrode négative pour les batteries Li-ions ou comme éponge à hydrogène dans les piles à combustibles.
Du point de vue fondamental, il s’agit de mettre en lumière la chimie et les propriétés en stockage de
l’énergie de ces nouvelles familles de nanomatériaux .
Techniques utilisées :
XRD, SEM, EDS, TEM, Tg, DSC, BET, IR, Electrochimie :
cyclage galvanostatique, potensiostatique GITT…..
Condition de recrutement
Titulaire d’un Doctorat en Chimie ou Physique des Matériaux, le candidat doit avoir moins de 35 ans et
ne pas avoir préparé sa thèse en France ou travailler actuellement en France.
Post-Doc rémunéré par le Ministère de la Recherche et de la Technologie,
12 mois, 1830 € net/mois, poste à pourvoir début septembre.
Envoyer un CV détaillé comprenant un résumé de l’activité de recherche et une liste des publications et
brevets.
Date limite de dépôt des candidatures : le lundi 07 avril 2003
Laboratoire d’accueil français :
Laboratoire de Réactivité et de Chimie des Solides (LRCS) UMR 6007
Université de Picardie Jules Verne (UPJV) , 33 rue Saint leu 80039 Ville : Amiens
http://www.u-picardie.fr/labo/lrcs
Encadrement assuré par Luc Aymard, Maître de Conférences à L’UPJV, chercheur au Laboratoire de
Réactivité et de Chimie des Solides.
mailto:Luc.aymard@u-picardie.fr
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-6-
Post Doc Proposal
Titre : Postdoctoral research fellowship on the elaboration of nanomaterials by supercritical fluid
processing – Bordeaux (France)
Contact : mailto:cansell@icmcb.u-bordeaux.fr
The Institut of Condensed Matter Chemistry of Bordeaux (ICMCB) proposes a post-doctoral research
fellowship. ICMCB (200 people) is a French laboratory of CNRS (French National Center for Scientific
Research) with research activities in Solid state chemistry, Material science and Molecular sciences.
The research project concerns the elaboration of nanomaterials by supercritical fluid processing in using a
new synthesis reactor equipped with an in situ analysis system by fluorescence spectroscopy. The aim
consists to synthesize ferroelectric nanomaterials with controlled size and surface properties. In particular,
we plan to study the nanoparticle size evolution as a function of the synthesis process working conditions
(Pressure, Temperature, residence time,…) by means of fluorescence spectroscopy. The ferroelectric
properties of the obtained nanomaterials will be studied and a correlation between nanoparticle size,
nanoparticle surface properties and material ferroelectric properties will be established.
The post-doctoral student will work with two well known teams of ICMCB and so, will dispose of a very
important human and technical potential.
The post-doctoral student must have a good expertise in material science, more precisely, in material or
nanomaterial synthesis and characterization and in material surface characterization.
The postdoctoral fellowship is supported by CNRS (2050 euros per month) for 12 or 18 months.
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-7-
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Congress and School Announcements
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J2IM 2003
Vogüé, ARDECHE (France)
19-21 mai 2003
http://www.emse.fr/fr/actualites/j2im2003.html
--------------------------------------------------
The 10th Int. Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials,
ISMANAM 2003,
will be held in Foz do Iguacu,
Brazil, on 24-28 August 2003
mailto:ismanam2003@dema.ufscar.br
http://www.dema.ufscar.br/ismanam2003
--------------------------------------------------
International Conference
NANOMATERIALS AND NANOTECHNOLOGIES (NN 2003),
Crete, Greece; August 30 - September 6, 2003
http://www.ipme.ru/ipme/conf/NN2003/
-------------------------------------------------INTERNATIONAL CONFERENCE
"Novel Technologies in Powder Metallurgy and Ceramics"
September 8-12, 2003
Kiev, Ukraine
--------------------------------------------------
Fourth INTERNATIONAL CONFERENCE
ON MECHANOCHEMISTRY AND MECHANICAL ALLOYING
4th INCOME 2003
Technical University of Braunschweig, Braunschweig, Germany
September 7-11, 2003
Website : http://www.tu-bs.de/INCOME2003
-------------------------------------------------11th FORESIGHT CONFERENCE ON MOLECULAR NANOTECHNOLOGY
October 9-12, 2003
San Francisco Airport Marriott
Burlingame, CA, USA
http://www.foresight.org/Conferences/MNT11
--------------------------------------------------
XV. International Symposium on Reactivity of Solids:
Nov. 9. - 13. 2003
Website : http://www.ISRSKYOTO.org/
mailto:info@ISRSKYOTO.org
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-8-
Périodiques / Congrès
[44] MECHANICAL BEHAVIOR AT 300-4.2 K OF BULK NANOSTRUCTURED TITANIUM PROCESSED BY SEVERE
PLASTIC DEFORMATION
Bengus VZ. Tabachnikova ED. Natsik VD. Miskuf J. Csach K. Stolyarov VV. Valiev RZ. - Physics of Metals &
Metallography (English Translation of Fizika Metallov i Metallovedenie). 94(Suppl 1):S11-S23, 2002.
The low temperature plasticity and failure of polycrystals of coarse-grained (CG) and nanostructured (NS) titanium of
commercial purity (VT1-0) were studied. The NS titanium was prepared by equal-channel angular pressing (ECAP) and
subsequent thermomechanical treatment. Two structural modifications were prepared, which had 0.3-mum and 0.1 mum grains.
The measurements were made at 300, 77, and 4.2 K under uniaxial compression at a strain rate of 4 x 10(-4) s(-1). The workhardening stress-strain curves were obtained; the macroscopic yield stress and the plasticity reserve were measured for samples
compressed along (parallel to) and across (perpendicular to) the ECAP axis. The yield stress increased by a factor of 1.5-2 on
changing from CG to NS titanium and on cooling from 300 to 4.2 K. Plasticity anisotropy was also observed in NS titanium
when the orientation of the compression axis was changed from parallel (parallel to) to perpendicular (perpendicular to); the
yield stress increased by a factor of 1.2-1.5. These changes in the sample structure and experimental conditions systematically
reduced the plasticity reserve, but the prefailure strain was still above 4%. No cold brittleness was observed in NS titanium
down to liquid-helium temperature, although at 4.2 K the plastic flow became jumplike, as in CG titanium. It is found that,
under low-temperature uniaxial compression, the failure of NS titanium is caused by the unstable plastic shear, leading to local
adiabatic heating of the material. This is not characteristic for CG titanium. Scanning electron microscopy of the shear-failure
surface morphology detected a characteristic "vein" pattern indicative of local heating to 800degreesC and higher. An analysis
of the experimental results prompts the following conclusions: (i) at low temperatures, plastic deformation in NS titanium is a
thermally activated process; (ii) the yield stress is influenced significantly by the microstructural internal stresses induced by
thermal anisotropy and by probable microtwinning; (iii) the grain-boundary shears play an important role in deformation and
failure processes
[43] DEVELOPMENT OF METHODS OF SEVERE PLASTIC DEFORMATION FOR THE PRODUCTION OF HIGHSTRENGTH ALLOYS BASED ON TITANIUM NICKELIDE WITH A SHAPE-MEMORY EFFECT
Pushin VG. Stolyarov VV. Valiev RZ. Kourov NI. Kuranova NN. Prokof'ev EA. Yurchenko LI. - Physics of Metals &
Metallography (English Translation of Fizika Metallov i Metallovedenie). 94(Suppl 1):S54-S68, 2002.
A brief review of the investigations of the authors concerning the application of methods of severe plastic deformation (SPD)
for the production of nanostructured alloys on the basis of titanium nickelide with a thermomechanical memory is presented.
For the first time, high-strength nanostructured TiNi-based alloys were obtained using several different SPD techniques,
including (1) multiple torsion under a high pressure, (2) multiple equal-channel angular pressing, and (3) multiple deformation
by rolling and drawing with intermediate annealings. It is shown that a special place among these techniques belongs to the
process of controlled nanocrystallization during annealing of alloys in the initially amorphous state that is ensured by severe
cold plastic deformation. The main features of structural states of SPD-processed alloys and their thermal stability are analyzed
using X-ray diffraction and transmission electron microscopy, including experiments in situ. The time temperature conditions
of nanocrystallization of amorphous TiNi-based alloys and the critical temperatures and sequence of martensitic
transformations were established and their dependence on the mode and amount of deformation and average grain size was
determined. The main structural mechanisms of the nucleation and growth of martensitic phases (R, B19', and B19) and their
morphology in nanostructured SPD-processed alloys based on TiNi were revealed. The temperature dependences of the
electrical resistivity and the mechanical properties of nanostructured alloys subjected to severe plastic deformation were
measured
[42] SEVERE PLASTIC DEFORMATION OF R-FE-B (R = PR OR ND) HARD MAGNETIC ALLOYS
Popov AG. Gaviko VS. Shchegoleva NN. Puzanova TZ. Ermolenko AS. Stolyarov VV. Gunderov DV. Raab GI. Valiev
RZ. - Physics of Metals & Metallography (English Translation of Fizika Metallov i Metallovedenie). 94(Suppl 1):S75-S81,
2002.
The results of investigations of the effect of severe plastic deformation on the structure and magnetic hysteresis properties of RFe-B (R = Pr or Nd) alloys are reviewed. Apart from grain refinement, the R2Fe14B phase decomposes to form an R-rich
amorphous phase and nanocrystalline (alpha-Fe. Annealing of heavily deformed alloys at temperatures T-a > 500degreesC
recovers the R2Fe14B phase in its nanocrystalline state, which significantly increases the coercive force of such alloys.
Annealing at 300 < T-a < 500degreesC of alloys with intermediate degrees of deformation, which mainly consist of elastically
stressed grains of the R2Fe14B phase, induces additional decomposition of this phase and a corresponding decrease in H-c. To
fabricate large bulk magnets, equal-channel angular pressing is used.
[41] STUDY OF A NANOCRYSTALLINE FE-C ALLOY COMPACTED BY SEVERE PLASTIC DEFORMATION OF POWDER
AFTER BALL MILLING
Krasil'nikov NA. Ivanisenko YV. Raab GI. Valiev RZ. - Physics of Metals & Metallography (English Translation of Fizika
Metallov i Metallovedenie). 94(Suppl 1):S91-S97, 2002.
Nanostructured Fe-1 wt % C samples characterized by a nearly theoretical density and a high strength were compacted by
severe plastic deformation of the powder obtained by ball milling. Study of the samples showed that their high density and
strength are determined by the compacting conditions, the nanocrystalline structure of the powder, and phase transformations
occurring upon severe plastic deformation
[40] STRUCTURAL FEATURES, STRENGTH, AND MECHANISMS OF DEFORMATION OF NANOCRYSTALLINE
MATERIALS
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
-9Noskova NI. - Physics of Metals & Metallography (English Translation of Fizika Metallov i Metallovedenie). 94(Suppl
1):S119-S130, 2002.
Results of recent original studies of the structure and properties of nanocrystalline metals and alloys produced by severe plastic
deformation and by nanocrystallization of amorphous alloys are considered. High resolution transmission electron microscopy,
scanning electron microscopy, and in situ deformation in the column of an electron microscope were used to analyze the
structural features and the mechanisms of plastic deformation of nanocrystalline materials.
[39] TOUGHENING OF MOSI2 DOPED BY LA2O3 PARTICLES
Zhang H. Wang DZ. Chen SP. Liu XY. - Materials Science & Engineering A-Structural Materials Properties Microstructure
& Processing. 345(1-2):118-121, 2003
Molybdenum disilicide (MoSi2) with or without La2O3 particles were synthesized by mechanical alloying (MA) and HP
techniques. The fracture toughness at room temperature was measured by Anstis' mode and the responded microstructures were
analyzed by using SEM and X-ray. The results show that the addition of La2O3 could obviously toughen the matrix. When the
content of La2O3 in MoSi2 is about 0.9%, the fracture toughness value increases by about 50% more than that of pure MoSi2.
We think, the corresponding toughening mechanisms depend on the following: fine-grain, microcracking, crack deflection,
crack microbridging, crack bowing and branching.
[38] MECHANOCHEMICAL SYNTHESIS OF PZT POWDERS
Brankovic Z. Brankovic G. Jovalekic C. Maniette Y. Cilense M. Varela JA. - Materials Science & Engineering A-Structural
Materials Properties Microstructure & Processing. 345(1-2):243-248, 2003
PZT ceramic powders were successfully prepared from the mixture of PbO, ZrO2 and TiO2 by mechanochemical synthesis in a
planetary ball mill, under different milling conditions. Phase evolution during synthesis was monitored by X-ray diffraction
analysis. Intensive milling resulted in formation of the nanocrystalline, perovskite PZT powders after 1 h of milling. This is a
significant improvement in comparison to milling conditions reported by other authors. Depending on milling parameters the
presence of some other phases, such as unreacted ZrO2, was also detected in some samples. The changes in powder size and
morphology due to intensive milling, were determined by SEM and TEM, while BET analysis was used to determine specific
surface area of the powders. Conclusions about processes taking place during mechanochemical synthesis of PZT powders
were made based on the results of characterization.
[37] EFFECT OF PHASE TRANSFORMATION DURING HIGH ENERGY MILLING ON FIELD ACTIVATED SYNTHESIS OF
DENSE MOSI2
Sannia M. Orru R. Garay JE. Cao G. Munir ZA. - Materials Science & Engineering A-Structural Materials Properties
Microstructure & Processing. 345(1-2):270-277, 2003
The effect of mechanical activation through high-energy ball milling of reactant powders on the subsequent synthesis of MoSi2
by field activation was investigated. Field activated synthesis of this silicide was made through the use of the spark plasma
sintering (SPS) method using a pulsed DC current. Milling (0-6 h) produced significant changes in the dispersion and
crystallite size of the reactants initially, and resulted in the;partial formation of the product in both the low-temperature (alpha)
and high-temperature (beta) modifications when longer milling times were employed. The sequence of phase evolution during
milling was determined from XRD, EDX and SEM analyses. Subsequent field-activated synthesis resulted in the formation of
alpha-MoSi2 only. The initiation of the synthesis reaction required a threshold power level (equivalent to the level of the
current), with the threshold decreasing with increased milling time. However, the initiation time increased when milling
resulted in the formation of a significant amount the product phase, with the increase being markedly significant at low power
levels.
[36] PARTICIPATION OF DIFFUSION IN THE PROCESSES OF MECHANICAL ALLOYING
Shtremel' MA. - Metal Science & Heat Treatment. 44(7-8):324-327, 2002
[35] OXIDATION BEHAVIOR OF MECHANICALLY ACTIVATED GALENA IN THERMOGRAVIMETRY (TG)
Hu HP. Chen QY. Yin ZL. Zhang PM. Tang AD. - Thermochimica Acta. 395(1-2):139-144, 2003
The oxidation behaviors of non-activated and mechanically activated galenas were investigated by thermogravimetry method
(TG) in flowing highly pure oxygen atmosphere at the heating rate of 10 K min(-1). It is found that the mass increase between
400 and 850 K in the TG curves rises with the increase of grinding time of galena. The difference in oxidation reactivity of
non-activated and mechanically activated galenas was also discussed. The specific granulometric surface area (S-G) and the
structural disorder of mechanically activated galenas were analyzed by X-ray diffraction laser particle size analyzer and X-ray
powder diffraction analysis (XRD), respectively. The results show that the specific granulometric surface area (S-G) of
mechanically activated galenas almost remains constant after grinding for a certain period, and lattice distortions (6) increase,
but the crystallite sizes (D) decrease with the increase of the grinding time. All the results imply that the mass increase between
400 and 850 K in the TG curves for mechanically activated galenas is mainly caused by the increase of lattice distortions (a)
and the decrease of the crystallite sizes (D) with increasing the grinding time
[34] EFFECTS OF MECHANOCHEMICAL ACTIVATION AND ALPHA-FE2O3 ADDITION ON THE FORMATION OF
CORUNDUM IN THERMAL TRANSFORMATIONS OF GAMMA-AL(OH)(3)
Tolchev AV. Kleshchev DG. Lopushan VI. - Russian Journal of Applied Chemistry. 75(9):1384-1388, 2002
Transformations of hydrargillite gamma-Al(OH)(3) during mechanochemical activation in various grinding mills and further
calcination of activated samples at 200-1300degreesC were studied. The effects of mechanochemical activation and additions
of iron(III) oxide compounds on the temperature of corundum formation and on its crystal size distribution were studied
[33] APPLICATION OF EXELFS SPECTROSCOPY TO THE STUDY OF THE LOCAL ATOMIC STRUCTURE OF CARBONCONTAINING MATERIALS
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 10 Maratkanova AN. Huang JY. Rats YV. Surnin DV. - Physics of Metals & Metallography (English Translation of Fizika
Metallov i Metallovedenie). 94(6):598-605, 2002
The main aim of this work was to further develop the method of extended energy-loss fine structure (EXELFS) for the
investigation of the structure of binary compounds containing light elements (C, 0, S, P, etc.). The local atomic structure m
different carbon modifications such as highly oriented pyrolytic graphite and amorphous graphite prepared by milling in a
planetary ball mill was studied in an HF-3000 FEG TEM transmission electron microscope equipped with an electron
spectrometer for recording electron-energy-loss spectra. The advantage of the EXELFS method for the study of the local
atomic structure of binary compounds containing light elements was demonstrated by the example of cementite Fe3C in a
carbon steel U15.
[32] EVOLUTION OF MICROSTRUCTURE AND MECHANICAL PROPERTIES OF IN SITU CONSOLIDATED BULK
ULTRA-FINE-GRAINED AND NANOCRYSTALLINE ZN PREPARED BY BALL MILLING
Zhang X. Wang H. Scattergood RO. Narayan J. Koch CC. - Materials Science & Engineering A-Structural Materials
Properties Microstructure & Processing. 344(1-2):175-181, 2003
The evolution of the microstructure and mechanical properties of ultra-fine-grained and nanocrystalline Zn induced by ball
milling at room temperature are studied systematically. The yield stresses measured from miniaturized disk bend tests and
tensile tests are consistent with the microhardness results and generally increase with the decrease of average grain size. A
dramatic decrease of hardness during milling from 1 to 3 h is a reflection of the increase of average grain size from 80 to 240
nm due to the initial unstable grain size and therefore, grain growth in this period. Young's modulus remains almost the same
for samples milled for different times and is that for conventional grain size Zn. A transition from bending to membrane
stretching is observed in the force-displacement curves for Zn ball milled for less than or equal to18 h. The variation of
transition strain with milling time could be related to the evolution of grain size distribution and therefore hardness during
milling
[31] COMBINATION OF MECHANICAL ALLOYING AND TWO-STAGE SINTERING OF A 93W-5.6NI-1.4FE TUNGSTEN
HEAVY ALLOY
Soon HH. Ryu HJ. - Materials Science & Engineering A-Structural Materials Properties Microstructure & Processing. 344(12):253-260, 2003
The microstructural evolution and mechanical properties of a mechanically alloyed and two-stage sintered tungsten heavy alloy
were investigated. Elemental powders of tungsten, nickel and iron of a composition corresponding to 93W-5.6Ni-1.4Fe were
mechanically alloyed in a tumbler ball mill for 72 h. Mechanically alloyed powders were solid-state sintered at 1300 degreesC
for 1 hr in a hydrogen atmosphere followed by secondary sintering at 1445-1485 degreesC for a sintering time ranging from 4
to 90 min. Solid-state sintered tungsten heavy alloys exhibited full densification (above 99% in relative density) due to the
enhanced sintering resulting from mechanical alloying. Secondary sintering with a rapid heating rate changed the
microstructures of the solid-state sintered alloy with contiguous tungsten phases into a dispersion alloy with spherical tungsten
particles embedded in the W-Ni-Fe matrix, maintaining fine tungsten particle due to the combination of a mechanical alloying
and a short sintering time. The two-stage sintered tungsten heavy alloy from mechanically alloyed powders showed finer
tungsten particle (about 6 mum in diameter) than in conventional liquid-phase sintered tungsten heavy alloys. The mechanical
properties of a tungsten heavy alloy were found to be dependent on the microstructural parameters such as tungsten particle
size, matrix volume fraction and tungsten/tungsten contiguity which are controllable through the two-stage sintering process.
[30] A NOVEL PROCESSING ROUTE TO DEVELOP A DENSE NANOCRYSTALLINE ALUMINA MATRIX (< 100 NM)
NANOCOMPOSITE MATERIAL
Zhan GD. Kuntz J. Wan J. Garay J. Mukherjee AK. - Journal of the American Ceramic Society. 86(1):200-202, 2003 Jan.
Abbreviated Source J. Am. Ceram. Soc. 86(1):200-202, 2003
A dense 3-mol%-yttria-stabilized tetragonal zirconia polycrystalline (3Y-TZP) toughening alumina matrix nanocomposite with
a nanocrystalline (<100 nm) matrix grain size has been successfully developed by a novel processing method. A combination
of very rapid sintering at a heating rate of 500degreesC/min and at a sintering temperature as low as 1100degreesC for 3 min
by the spark-plasma-sintering technique and mechanical milling of the starting gamma-Al2O3 nanopowder via a high-energy
ball-milling process can result in a fully dense nanocrystalline alumina matrix ceramic nanocomposite. The grain sizes for the
matrix and the toughening phase were 96 and 265 nm, respectively. A great increase in toughness almost 3 times that for pure
nanocrystalline alumina has been achieved in the dense nanocomposite. Ferroelastic domain switching without undergoing
phase transformation in nanocrystalline t-ZrO2 is likely as a mechanism for enhanced toughness.
[29] STRUCTURAL STABILITY OF MECHANICALLY ALLOYED (MG+10NB) AND (MGH2+L0NB) POWDER MIXTURES
Shang CX. Bououdina M. Guo ZX. - Journal of Alloys & Compounds. 349(1-2):217-223, 2003
In order to improve the hydrogen storage characteristics of magnesium, both chemical alloying by Nb and mechanical alloying
(MA) of (Mg +10 wt. %Nb) and (MgH2+10 wt.%Nb) powder mixtures were investigated, with particular attention paid to their
structural stability. Extensive powder refinement was noted for both compositions within 20 h of milling at 250 rpm. Even
nano-sized particles were generated in the hydride mixture. XRD and Rietveld analyses show the formation of a bcc phase in
each case. The amount of the bcc phase increases with increasing milling time to the detriment of Nb. For the (Mg +10 wt.
%Nb) mixture, it is confirmed that the newly formed phase is a bcc-(Nb,Mg) solid solution, with an extended solubility of Nb
in Mg. However, for the (MgH2 + 10 wt.%Nb) powder mixture, the new bcc phase can be a Nb hydride (NbHx, x < 1.0), or a
bcc-(Nb,Mg) solid solution, or a (Nb,Mg)H-x solid solution, or even a mixture of the three.
[28] PREPARATION OF SODIUM BOROHYDRIDE BY REACTION OF MGH2 WITH DEHYDRATED BORAX THROUGH
BALL MILLING REACTION OF MGH2 WITH AT ROOM TEMPERATURE
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 11 Li ZP. Morigazaki N. Liu BH. Suda S. - Journal of Alloys & Compounds. 349(1-2):232-236, 2003
A convenient method was developed to synthesize NaBH2 by the reaction of MgH2 with Na2B4O7 through ball milling at
room temperature. In order to improve the sodium borohydride yield, Na compounds were added to compensate the Na
insufficiency in reactants when MgH2 instead of NaH was used as the reducing agent. It was found that Na2CO3 addition was
better than NaOH or Na2O2 addition in increasing the borohydride yield
[27] OPTIMISATION OF THE BALL-MILLING AND HEAT TREATMENT PARAMETERS FOR SYNTHESIS OF
AMORPHOUS AND NANOCRYSTALLINE MG2NI-BASED ALLOYS
Spassov T. Solsona P. Surinach S. Baro MD. - Journal of Alloys & Compounds. 349(1-2):242-254, 2003
Amorphous and nanocrystalline Mg1.9M0.1Ni (M=Ti,ZrV) alloys were synthesized by mechanical alloying (MA) and by MA
followed by annealing. The phase composition, microstructure and morphology of the as-milled powder, and the milled and
heat treated powders were determined by XRD and SEM/EDX. Thermal stability, crystallization and grain growth processes in
the nano-/amorphous alloys were investigated too. The milling and heat treatment conditions for obtaining amorphous or
nanocrystalline alloys were optimised for different alloy compositions. After milling or milling with annealing the ternary and
quaternary alloys have the hexagonal Mg2Ni crystal structure with crystallite sizes in the range of 5-15 nm, depending on the
conditions of milling and annealing. The microstructure of the alloys obtained by long time milling is much finer compared to
that of the shorter time milled samples, both subjected to annealing after milling. The grain size of the final nanostructures
increases slightly during heating to above 400 degreesC. The nanocrystalline Mg2Ni-based alloys prepared by extended
milling show higher thermal stability than the short time milled alloys.
[26] EFFECT OF EXTENDED BALL MILLING ON GRAPHITE
Welham NJ. Berbenni V. Chapman PG. - Journal of Alloys & Compounds. 349(1-2):255-263, 2003
Graphite has been milled for up to 1000 It in a laboratory scale tumbling ball mill under vacuum. Raman spectroscopy of the
powders indicated the increasing dominance of D-type graphitic sp(2) bonding over G-type bonding with increasing milling
time. Diamond-like sp(3) bonding and possibly fullerene-like bonding also became evident after milling. TEM of the 100 It
sample showed the presence of ribbons which were composed of sheets showing defects, delamination, translation, warping
and curvature. Interplanar spacings of 0.40-0.50 nm were measured with the spacing increasing towards the edge of the ribbons
where delamination was evident. Thermogravimetric analysis in argon of the powder after exposure to air showed an increasing
mass loss with milling time indicating the presence of chermsorbed gas. Using TG-FTIR the gas was found to be a mixture of
CO2 and an unidentified gas (probably oxygen). BET surface area measurements showed a maximum in the surface area;
however, this was shown to be massively in error for the longer milling times due to the presence of the chemisorbed gas.
[25] THE EFFECT OF GRAIN REFINING ON THE DISCHARGE CAPACITY OF MG2NI/MMNI(5-X)(COALMN)(X)
COMPOSITE PREPARED BY MECHANICAL ALLOYING
Zhu M. Wang ZM. Peng CH. ZEng MQ. Gao Y. - Journal of Alloys & Compounds. 349(1-2):284-289, 2003
Hydrogen storage composites were prepared by ball-milling the powder mixtures of Mg2Ni and MmNi(5-x)(CoAlMn)(x)
(denoted as MmM(5)) alloys. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis show that the
particles of Mg2Ni/MmM(5) nanophase composite are aggregates of constituent phases. The electrode properties of Mg2Ni
alloys, MmM(5) alloy and nanophase composites with different grain sizes were measured by simulation battery test. It was
found that the discharge capacity of Mg2Ni alloy was enhanced with increased milling time, but decreased with milling time
for MmM(5) alloy. As for the nanophase composite, its discharge capacity was not simply the linear sum of the capacities of
components constituting the composite. An enhancement effect on capacity has been observed in the composite when the grain
size of the phase inside the composite is less than about 100 nm
[24] ELECTROCHEMICAL PROPERTIES OF NIS AS A CATHODE MATERIAL FOR RECHARGEABLE LITHIUM
BATTERIES PREPARED BY MECHANICAL ALLOYING
Han SC. Kim HS. Song MS. Lee PS. Lee JY. Ahn HJ. - Journal of Alloys & Compounds. 349(1-2):290-296, 2003
Nickel sulfide (NiS) as a cathode material for a lithium rechargeable battery is charged and discharged at room temperature (30
degreesC). In order to synthesize a homogeneous NiS phase, mechanical alloying (MA) was adopted. The homogeneous NiS
phase is easily formed after ball milling for 12 h under Ar atmosphere. The ball-milled NiS particles are relatively larger than
those of the starting materials and have a nanocrystalline structure. The initial discharge capacity of the NiS positive electrode
is 580 mAh/g-NiS, at 1.4 V versus Li/Li+. The NiS powders synthesized by MA show proper cycling properties, by retaining
65% of the initial discharge capacity even after 100 cycles at 30 degreesC. Also, NiS has a good rate capability. It has 87% of
its theoretical capacity at a current rate of 2 C, comparable with that of 1/6 C
[23] STRUCTURE
MAGNETS
AND
MAGNETIC
PROPERTIES
OF
ND-2(FE,CO,AL,CR)(14)B/ALPHA-FE
NANOCOMPOSITE
Jakubowicz J. Giersig M. - Journal of Alloys & Compounds. 349(1-2):311-315, 2003
The structure, magnetic properties and corrosion behaviour of two-phase nanocomposite Nd-2(Fe,Co,Al,Cr)(14)B/alpha-Fetype magnets, which have tetragonal/cubic Nd2Fe14B/alpha-Fe structure, have been investigated. The magnetic hardening was
achieved by high-energy ball-milling (HEBM) of the Nd2Fe,,B-type hard magnetic phase with different vol.% of alpha-Fe as
soft magnetic phase, followed by annealing. Fully dense Nd-2(Fe,Co,Al,Cr)(14)B/alpha-Fe type magnets have been produced
by hot pressing. Magnets with good corrosion resistance as well as high temperature stability have been produced. The
corrosion resistance is improved in the case of Co-, Al-, Cr-doped nanocomposite magnets with a volume fraction of the soft
magnetic phase of 37.5 vol.%. Effective protection against corrosion was realised also by surface coating with Zn metal.
[22] AN IN SITU NEUTRON TIME-OF-FLIGHT DIFFRACTION STUDY OF LAMM(NICOALMN)(5-X) BATTERY
ELECTRODE MATERIALS AND THEIR DEUTERIDES, FOR X=0 AND X=0.2
Georgiev PA. Liu J. Ross DK. Andersen KH. Otto A. - Journal of Alloys & Compounds. 349(1-2):325-333, 2003
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 12 The structural properties of two mechanically activated commercial LaNi, type battery materials and their deuterides have been
investigated by means of in situ neutron powder diffraction analysis. A discussion of the hysteresis between the absorption and
desorption isotherms is given. Using standard Rietveld refinement procedures, information on the variation of the deuterium
site occupancy, the lattice symmetry and the cell volume are also presented. In particular, we report on the variation of linebroadening with concentration as well as on the complex time-dependent changes in the lattice parameters and the linebroadening following a step change in the deuterium pressure. We then show that these relatively novel data provide valuable
information on the rather different phase transition processes observed for the two materials and offer an explanation for the
superior kinetics of the AB(4.8) alloy.
[21] PREPARATION AND CHARACTERIZATION OF ACRYLIC/NANO-TIO2 COMPOSITE LATEX
He QY. Wu LM. Gu GX. You B. - High Performance Polymers. 14(4):383-396, 2002
Acrylic/nano-TiO2 composite latex samples were prepared via high-shear stiffing and mixing (SM), ball milling and mixing
(BM) and in situ polymerization (IS) methods, and investigated by transmission electron micrography (TEM), testing with an
Instron machine, dynamic mechanical analysis (DMA) and ultraviolet-visible (UV-VIS) spectrophotometry. It was shown that
the IS method led to the best dispersion of nano-TiO2 particles in acrylic copolymer films, the SM method was the second best
and the BM method gave the least good result. Addition of nano-TiO2 by SM and BM methods led to higher tensile strength
and T, for polymers than introduction with micro-TiO2 and without any fillers. UV-VIS spectra indicated that addition of
nano-TiO2 into acrylic copolymers could increase the absorbance and decrease the transmittance in the UV region, whereas the
absorbance or transmittance in the UV region basically remained unchanged for the composites filled with micro-TiO2 [20]
INFRARED STUDY OF MAGNESIUM-NICKEL HYDROXIDE SOLID SOLUTIONS
de Oliveira EF. Hase Y. - Vibrational Spectroscopy. 31(1):19-24, 2003
The IR spectra of the co-precipitated solid solutions MgxNi1-x(OH)(2) were studied in the 4000-40 cm(-1) region. The spectra
as a whole resemble those of Mg(OH)(2) and beta-Ni(OH)(2), while certain differences are noted when compared with the
spectra of the mechanically mixed samples Mg(OH)(2) + beta-Ni(OH)(2). Such a behavior may imply formations of monophase solid solutions which have a brucite-like crystal structure. The composition-dependent band shifts were observed for the
fundamentals and this tendency is discussed in terms of polarization of the O-H bond and partial covalency of the M-O bonds.
The gradual changes in band position of MgxNi(1-x)(OH)(2) (1.00 greater than or equal to x greater than or equal to 0.00)
were used to assign the IR active lattice modes of the solid solutions and to review the assignment of beta-Ni(OH)(2).
[19] SOLVENT-FREE REACTIONS OF FULLERENES AND N-ALKYLGLYCINES WITH AND WITHOUT ALDEHYDES
UNDER HIGH-SPEED VIBRATION MILLING
Wang GW. Zhang TH. Hao EH. Jiao LJ. Murata Y. Komatsu K. - Tetrahedron. 59(1):55-60, 2003
The solvent-free reactions of fullerenes and N-alkylglycines with and without aldehydes (RCHO) 2a-e under high-speed
vibration milling (HSVM) conditions have been investigated. Fulleropyrrolidines 4a-e (C-60(CH2N(CH3)CHR), R=H (4a),
C6H5 (4b), pNO(2)-C6H5 (4c), p-CH3O-C6H4 (4d), p-(CH3)(2)N-C6H4 (4e)) were obtained in moderate yields from
reactions of C-60 with aldehydes 2a-e and N-methylglycine (Prato reaction). In all these solvent-free reactions, 4a was found to
be formed besides 4b-e, indicating that fullerenes can react with N-substituted glycines in the absence of aldehyde to give
fulleropyrrolidines. For this novel reaction, a possible reaction mechanism involving an electron transfer process has been
proposed. Intrigued by this observation, the dependence of the yield on the reagent ratio for the reaction of C-60 with
paraformaldehyde and/or N-methylglycine was examined to search the optimal conditions. The reaction of C-70 with
paraformaldehyde and/or N-methylglycine under HSVM conditions was also studied and was found to give the positional
isomers of [70]fulleropyrrolidines
[18] SOLID-PHASE SYNTHESIS OF ZINC(II) BETA-DIKETONATES UPON MECHANICAL ACTIVATION
Petrova LA. Borisov AP. Makhaev VD. - Russian Journal of Inorganic Chemistry. 47(12):1827-1832, 2002
Mechanically activated solid-phase reactions between zinc chloride and sodium beta-diketonates are studied. The course of the
reaction, the product yield, and some properties of the activated mixtures are studied in relation to mechanical treatment
conditions and the nature of beta-diketone. Zinc beta-diketonates are separated by sublimation from the activated mixtures in
>70% yield. Unsolvated zinc beta-diketonates are characterized by physicochemical methods.
[17] CHARACTERISTICS OF POLYVINYLPYRROLIDONE-LAYERED SILICATE NANOCOMPOSITES PREPARED BY
ATTRITION BALL MILLING
Koo CM. Ham HT. Choi MH. Kim SO. Chung IJ. - Polymer. 44(3):681-689, 2003
Polyvinylpyrrolidone (PVP)/sodium montmorillonite (MMT) nanocomposites prepared via the solution intercalation method
were investigated by UV/vis, SEM, X-ray diffraction, TEM, FT-IR and PLM (polarized light microscopy). PVP/MMT
nanocomposites show exfoliation below 20 wt% MMT and intercalation above this concentration. Nanocomposites retain good
optical clarity and increased thermal resistance with MMT content. The compatibility between PVP and MMT and their
enhanced properties may be explained by hydrogen bonding interactions. In addition, the nanocomposites prepared under more
rigorous mixing conditions show better transparency because the smaller particle sizes are induced. In addition, the study on
optically clear PVP/MMT suspensions helps one to understand how optical anisotropy of MMT is affected by the existence of
polymer in. aqueous solution
[16] EVOLUTION OF VACANCY DENSITIES IN POWDER PARTICLES DURING MECHANICAL MILLING
Zhang BQ. Lu L. Lai MO. - Physica B: Condensed Matter. 325(1-4):120-129, 2003
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 13 This paper investigates the change in the density of vacancies during ball milling. A model for the evolution of vacancies has
been proposed in this paper. Results from the simulation show that the density of vacancies increases asymptotically with
collision times and the rate of increase becomes slower with further ball milling. The accumulation of vacancies in the powder
particles is dramatically accelerated at lower milling temperature. Vacancies are shown to accumulate more easily in powder
materials with higher vacancy migration energies. The present simulation indicates that higher collision frequency results in a
faster accumulation of vacancies and therefore higher density of vacancies can be obtained. In addition, higher impact energy
introduces higher density of vacancies per collision. Low milling temperature, high collision frequency and high collision
energy may be advantage for the formation of new alloys, but low migration rate of vacancies at low temperature may reduce
the rate of the formation of new alloys if the milling temperature is too low.
[15] ON THE INFLUENCE OF N ON RESIDUAL MICROSTRAIN IN CRYOMILLED NI
Chung KH. Lavernia EJ. - Metallurgical & Materials Transactions A-Physical Metallurgy & Materials Science. 33(12):37953801, 2002
The factors that influence the development of residual microstrain during milling in a liquid nitrogen atmosphere, defined
hereafter as cryomilling, are investigated. The residual microstrains in cryomilled Ni, processed under various cryomilling
conditions, were examined by X-ray diffraction (XRD) and analyzed through the single line approximation (SLA) method. The
average residual microstrains are determined to be in the range of 2 X 10(-3) to 6 X 10(-3). The residual microstrain on the
(200) plane is higher than those on the other planes by 33 pct. The residual microstrain and its anisotropy in Ni are reduced
after heat treatment at 800 degreesC for 1 hour. The measured microstrain is proposed to evolve from the presence of N and O
as impurity atoms in the Ni lattice. Both N and O are introduced from the environment and then their solubility in Ni is
enriched via the generation of defects that occurs during cryomilling. The stable site for N and O atoms in Ni is the octahedral
site, and the sizes of N and O atoms exceed those of the octahedral site of Ni by 48 and 16 pct respectively. Accordingly, a
lattice strain field is expected around interstitial N atoms that are located at octahedral sites. By comparing the crystal structure
around the octahedral site, the stable site for impurity N atoms, in the Ni lattice with that of Ni3N structure, the lattice strains
are estimated to be in the range of 5 to 15 pct. The result shows that the (200) plane has strains that are 2 times higher than
those in other planes, and this is argued to be the reason for the measured anisotropy of residual strain in Ni after cryomilling
[14] MICROSTRUCTURE AND MAGNETIC PROPERTIES OF NANOSIZED FE-CO ALLOY POWDERS SYNTHESIZED BY
MECHANOCHEMICAL AND MECHANICAL ALLOYING PROCESS
Lee BH. Ahn BS. Kim DG. Oh ST. Jeon H. Ahn J. Kim YD. - Materials Letters. 57(5-6):1103-1107, 2003
An optimum route to synthesize nanosized Fe-Co alloy powder with enhanced magnetic properties was investigated. Two
methods of mechanical alloying (MA) and mechanochemical alloying (MCA) for developing a nanosized alloy powder were
compared on the basis of the resulting microstructural characteristics and magnetic properties. The alloy powder, synthesized
by MCA process with ball milling and hydrogen reduction using Fe2O3 and Co3O4 powders, showed ordered BCC structure
with the grain size of 40 nm. Also, this powder exhibited low coercivity of 43 Oe and good permeability compared with MA
powder. Enhanced magnetic properties of the MCA powder were explained by the formation of ordered structure and
relaxation of internal strain
[13] MECHANOCHEMICAL REACTIONS BETWEEN AG2O AND V2O5 TO FORM CRYSTALLINE SILVER VANADATES
Kittaka S. Nishida S. Ohtani T. - Journal of Solid State Chemistry. 169(1):139-142, 2002
Solid-state reactions between Ag2O and V2O5 were studied under ball-milling conditions. Single-phase crystalline Ag4V2O7
was formed from the mixture of Ag2O and V2O5 of corresponding (2:1) composition. The main component in the product
when the Ag2O mole fraction is less than V2O5 is amorphous AgVO3, which is crystallized into needle-like alpha-AgVO3 in
the presence of water. Excess V2O5 was hydrated into V2O5 . nH(2)O intercalated with Ag+ ions. The mixtures with more
than two parts of Ag2O relative to V2O5 are composite materials of Ag4V2O7 and Ag3VO4, together with Ag2O. The
crystalline phases in these systems resist attack by water.
[12] FRACTURE ANALYSIS OF ALUMINUM MATRIX COMPOSITE MATERIALS REINFORCED WITH (NI3AL)P
Velasco F. Da Costa CE. Candela N. Torralba JM. - Journal of Materials Science. 38(3):521-525, 2003
This paper studies the influence of Ni3Al intermetallic particles on the fracture behaviour of aluminium matrix (2014)
composite materials. Intermetallics were obtained by mechanical alloying and by atomisation. The composite materials were
manufactured by mixing, uniaxial compacting of a preform, and subsequent extrusion without canning or degassing. The study
considered materials in extruded state and after T6 heat treatment. Assessments were made from the viewpoint of
microstructure (by means of optical and scanning electron microscopy), and studying the reactions between the matrix and the
reinforcement. These reactions produce a highly copper-enriched interphase. The influence of the reinforcement and state of
the alloy on the fracture behaviour of the composite materials was studied through scanning electron microscopy
[11] MICROSTRUCTURES AND MECHANICAL PROPERTIES OF ZRO2/NIAL MATRIX COMPOSITES ELABORATED
FROM MECHANOFUSION-PROCESSED POWDERS
Ouchetto M. Grosbras M. Chouiyakh A. - Journal of Materials Science. 38(3):589-595, 2003
ZrO2-coated NiAl powders have been elaborated using an innovative mill process, the so-called mechanofusion process.
Following processing conditions, different types of particles (size, morphology, degree of coating) can be obtained. These
powders were consolidated to full density by HIPping and mechanical tests were carried out on the various elaborated products
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 14 at temperatures ranging between 20-800degreesC. Results are compared to those previously obtained for ZrO2/NiAl
composites elaborated by conventional methods. It is shown that mechanical strength of ZrO2/NiAl composites can be
considerably improved by using the mechanofusion process.
[10] GRAIN GROWTH AND RECRYSTALLIZATION OF NANOCRYSTALLINE AL3TI PREPARED BY MECHANICAL
ALLOYING
Zhang F. Lu L. Lai MO. Froes FH. - Journal of Materials Science. 38(3):613-619, 2003
The grain sizes and lattice strains during mechanical alloying of Ti-75 at.% Al powder mixtures were studied using X-ray
diffraction methods. Nanocrystalline L1(2)-Al3Ti was obtained after a certain time period of ball milling. Minimum grain sizes
of 17 nm for Al and 28 nm for Ti have been determined using XRD. During subsequent thermal annealing processing, an
obvious recrystallization resulting in significant reduction of grain size was observed. The recrystallization in nanocrystalline
Al3Ti was affected by both the temperature and the degree of order. The incubation period for recrystallization at 400degreesC
was about 6 hours while those at 510 and 700degreesC were about 2 hours. The completion time of recrystallization in Al3Ti
at 400 and 700degreesC was about 15 hours and 8 hours at 510degreesC. It is clear that the recrystallization at 700degreesC
was retarded as a result of the higher degree of order structure which limited the mobility of the boundaries. Phase
transformation occurring within the recrystallization temperature range was observed to have little influence on the
recrystallization itself. However, transformation products do have significant effects on it which is originated from the degree
of order in the products. The recrystallization in this alloy system provides an excellent means to maintain the nanocrystalline
microstructure during the necessary consolidation thermal cycle by decreasing the processing temperature and increasing the
hold time considerably
[9] SYNTHESIS AND CONSOLIDATION OF TIAL BY MA-PDS PROCESS FROM SPONGE-TI AND CHIP-AL
Sun ZM. Wang Q. Hashimoto H. Tada S. Abe T. - Intermetallics. 11(1):63-69, 2003
Low cost sponge-Ti and recycled chip-Al were used as starting materials for the synthesis and consolidation of TiAl alloy via a
mechanical alloying (MA) and pulse discharge sintering (PDS) process. Amorphous structured TiAl powder was obtained by
MA process from sponge-Ti/chip-Al and was sintered and concurrently consolidated with the PDS process. The obtained TiAl
alloy consists of gamma-TiAl and alpha(2)-Ti3Al and additional Ti2AlC phase. The microstructure of the alloy can be
controlled by the sintering temperature. It was found that fine equiaxed grains were obtained by low temperature sintering
while fine duplex structures formed at high temperature sintering. Compared with alloys fabricated from high cost elemental
Ti/Al powder with a similar process, the alloys sintered at high temperature with this process possess much higher strength at
both room temperature and elevated temperatures.
[8] SYNTHESIS OF NANOCRYSTALLINE MOSE2 BY SONOCHEMICAL REACTION OF SE WITH MO(CO)(6)
Kristl M. Drofenik M. - Inorganic Chemistry Communications. 6(1):68-70, 2003
Nanocrystalline MoSe2 was prepared by a sonochemical reaction between Mo(CO)(6) and Se in decalin at 273 K in nitrogen
atmosphere. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM),
energy-dispersive X-ray spectroscopy (EDXS) and thermal analysis (TG and DSC). The XRD patterns showed that the product
is amorphous, while annealing at 330degreesC yields nanocrystalline MoSe2. The influence of ultrasound and temperature is
discussed
[7] EFFECTS OF MECHANICAL TREATMENT ON PHASE TRANSFORMATION AND SINTERING OF NANO-SIZED
GAMMA-FE2O3 POWDER
Hsiang HI. Yen FS. - Ceramics International. 29(1):1-6, 2003.
The effects of mechanical treatment on the phase transformation and sintering of nano-sized gamma-Fe2O3 powder were
studied. gamma-Fe2O3 powder was obtained by calcining iron tartrates at 300 degreesC. The mechanical treatment increased
the contact areas in thegamma-Fe2O3 powder, which acted as nucleation sites for the gamma-->alpha-Fe2O3 phase
transformation, and resulted in lowering the transformation temperature. The greater surface area and fine equiaxed particle of
the milled powder thus obtained were due to the vermicular microstructure development being inhibited. Consequently, the
samples with mechanical treatment after sintering developed a uniform fine-grained microstructure
[6] RE-CO/AL2O3 BIMETALLIC CATALYSTS PREPARED BY MECHANICAL TREATMENT: CO HYDROGENATION AND
CH4 CONVERSION
Guczi L. Takacs L. Stefler G. Koppany Z. Borko L. - Catalysis Today. 77(3):237-243, 2002
Re-Co/Al2O3 (M) bimetallic catalysts were prepared by ball milling in a high-energy shaker mill using a WC container and
four WC balls. The structure and activity of the Re-Co/Al2O3 (M) are compared to a Re-Co/Al2O3 (IM) sample prepared by
the incipient wetness technique. The mechanically treated sample contains disordered, probably partly amorphous metal
particles. Heat treatment of the Re-Co/Al2O3 (M) sample was carried out in hydrogen at 450 and 650 degreesC. It affects the
crystallinity and the catalytic properties of the metal particles. The rate measured for the CO hydrogenation over ReCo/Al2O3 (IM) catalyst is significantly higher than that measured over the Re-Co/Al2O3 (M) sample. On the other hand, in the
CH4 conversion to higher hydrocarbons, the Re-Co/Al2O3 (M) showed higher activity after treatment at 650 degreesC. The
opposite behavior of the M and IM samples is explained by the changing morphology of the active sites responsible for the two
different reactions.
[5] PREPARATION OF FUCTIONAL MATERIALS VIA NON-CONVENTIONAL ROUTES
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr
- 15 Senna M. - Annales de Chimie-Science des Materiaux. 27(6):3-14, 2002
An overview is given on the non-conventional solid-state processes for the preparation of functional materials. Emphasis is laid
on the formation of heterogeneous bridging bonds (BBB) across the boundary between two dissimilar solids under mechanical
stressing. Loss of the coordination number for the near surface atoms and/or disturbance of the symmetry of the crystal field or
the ligand field are discussed in conjunction with the BBB formation. Case studies on complex oxides, ferrous coordination
compounds and some organic - inorganic composites are given
[4] MECHANICALLY ACTIVATED POWDER METALLURGY PROCESSING: A VERSATILE WAY TOWARDS
NANOMATERIALS SYNTHESIS
Gaffet E. Bernard F. - Annales de Chimie-Science des Materiaux. 27(6):47-59, 2002
The mechanical activation of powder metallurgy processing has been shown to lead to the synthesis of nanostructured
micropowders (ERAM / M2AP process), homogeneous but porous nanomaterials (MASHS process). Recently, such an
activation step before self heat sustaining reaction has been found to lead to the synthesis of fully dense bulk nanostructured
materials (patented process, so called MAFAPAS
[3]
NANOCRYSTALLINE
MATERIALS
PREPARED
MECHANOCHEMICAL REACTIONS [REVIEW]
BY
HOMOGENEOUS
AND
HETEROGENEOUS
Sepelak V. - Annales de Chimie-Science des Materiaux. 27(6):61-76, 2002
At present, the high-energy milling method becomes widely used for the preparation of nanocrystalline materials due to its
relative simplicity and availability. In this overview, selected examples are presented of the preparation of nanoscale materials
by homogeneous and heterogeneous mechanochemical reactions, in spinet ferrites. Despite numerous, efforts, the
understanding of the nonequilibrium mechanochemical processes is considered to be far from complete, leaving large scope for
further research in this exciting field.
[2] SOFT MECHANOCHEMICAL SYNTHESIS: PREPARATION OF CATHODE MATERIALS FOR RECHARGEABLE
LITHIUM BATTERIES
Kosova N. Devyatkina E. - Annales de Chimie-Science des Materiaux. 27(6):77-90, 2002
To prepare intercalation lithium - transition metal oxide cathode materials for rechargeable lithium batteries, the reactions in
the mixtures of the correspondent hydroxides in highly energetic planetary activators, so called 'soft mechanochemical
synthesis', were studied. The method can be used for direct preparation of final products in a high dispersed and disordered
state, as well as for obtaining high reactive precursors yielding final products by the subsequent brief heating,at considerably
lower temperatures as compared to conventional ceramic method. The as prepared products were analyzed using X-ray
diffraction, TG, IRS, XPS, Li-7 NMR, EPR, diffuse reflectance spectroscopy, electron microscopy, BET, and electrochemical
measurements. The peculiarities of crystal structure, electronic state of transition metal ions and cycling behaviour of materials
are discussed. The method as proposed is concluded to be economically effective and ecologically clean.
[1] ROLE OF MOLECULAR STRAIN ON THE SOLID-STATE SYNTHESIS OF COORDINATION COMPOUNDS FROM
IRON(II) CHLORIDE TETRAHYDRATE AND 1,10-PHENANTHROLINE UNDER MECHANICAL STRESS
Ohshlta T. Nakajima D. Tsukamoto A. Tsuchiya N. Isobe T. Senna M. Yoshioka N. Inoue H. - Annales de Chimie-Science
des Materiaux. 27(6):91-101, 2002
A powdered crystalline mixture of iron(II) chloride tetrahydrate (FeCl(2.)4H(2)O) and 1,10-phenanthroline (phen) was
subjected to mechanical stressing in Ar by a planetary ball-mill. By milling for 3h, the mixture turned completely noncrystalline. New IR absorption bands appeared simultaneously at 358cm(-1) due to Fe-N(phen) stretching and at 207cm(-1)
due to N-Fe-N(phen) bending for [Fe(phen)(3)](2+). Only a doublet peak due to [Fe(pben)(3)]Cl-2.nH(2)O was detected m the
Mossbauer spectrum. All these results indicate consistently the formation of [Fe(phen)(3)]Cl-2.nH(2)O by milling with an
almost quantitative yield. Disproportionation of the hydrated water molecules was observed after milling FeCl2.4H(2)O alone
for 3h. The molecular strain triggers a solid-state exchange reaction between H2O and phen at the contact point of two
dissimilar solid particles under mechanical stressing, and promotes formation of [Fe(phen)(3)]Cl-2.nH(2)O in the solid state.
Lettre RFM N°97 - Avril 2003
Corresp. : mailto:Eric.Gaffet@utbm.fr